c# - 检索祖先属性

Question

我正在尝试为多个应用程序构建一个外部 XML 配置文件，以容纳它们的连接字符串。该文件看起来像这样:

<?xml version="1.0" encoding="ISO-8859-1"?>
<configuration>
  <Connection Name = "Primary">
    <Server Name = "DisneyWorld">
      <Database Name ="MagicKingdom">
        <Project Name ="Rides">
          <Login Username="Mickey" Password="Mouse" Encrypted="False"/>
        </Project>
        <Project Name = "Food">
          <Login Username="Goofy" Password="123456" Encrypted="True"/>
        </Project>
        <Project Name ="Shows">
          <Login Username ="Minnie" Password="Mouse" Encrypted="False"/>
        </Project>
      </Database>
    </Server>
    <Server Name = "Epcot">
      <Database Name ="LandOfTomorrow">
        <Project Name = "Innovation">
          <Login Username="Daffy" Password="Duck" Encrypted="False"/>
        </Project>
      </Database>
    </Server>
  </Connection>
</configuration>

将有一个辅助连接，以防主连接出现故障。我想要做的是搜索 Project: Food 获取其登录信息、数据库和服务器。我可以用这段代码来做:

XDocument doc = XDocument.Load(path);
var query = from connection in doc.Descendants("Connection")
            where connection.Attribute("Name").Value == "Primary"
            from project in connection.Descendants("Project")
            where project.Attribute("Name").Value == targetProject
            select new
            {
                Server = connection.Element("Server").Attribute("Name").Value,
                Database = project.Parent.Attribute("Name").Value,
                UserName = project.Element("Login").Attribute("Username").Value,
                Password = project.Element("Login").Attribute("Password").Value,
                Encrypted = project.Element("Login").Attribute("Password").Value
            };

除了硬编码到当前结构之外，代码运行良好。线上

Server = connection.Element("Server").Attribute("Name").Value,

和

Database = project.Parent.Attribute("Name").Value,

我希望能够从 project.Ancestors("Server") 中获取它们的值，但我知道如何实现这一点。

Answer 1

你的意思是:

Server = project.Ancestors("Server").Single().Attribute("Name").Value;
Database = project.Ancestors("Database").Single().Attribute("Name").Value;

当然，这是假设给定元素将永远只有一个祖先。